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CryptoHack

A free, fun platform for learning modern cryptography

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Learn By Doing

Learn about modern cryptography by solving a series of interactive puzzles and challenges. Get to know the ciphers and protocols that secure the digital world by breaking them.

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Level Up

Earn points by solving challenges. Finish categories to earn trophies and gain levels to track your progress. Can you reach the top of the scoreboard?

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Fresh Challenges

We are constantly creating new challenges to keep your crypto knowledge up to date. Expect exciting brainteasers and whole new categories as the site continues to grow.

New Challenges
Do you have good eyes? (Breizh CTF) CTF Archive 0
RSATogether (ECSC 2024 (Italy)) CTF Archive 0
Authentification 1 (Breizh CTF) CTF Archive 0
One Round Crypto (ECSC 2024 (Italy)) CTF Archive 0
Greatest Common Multiple (CODEGATE CTF) CTF Archive 0
Weekly Top Users
#1 Harachili 9180
#2 s4hm4d 3240
#3 ciphermalware 3025
#4 FrancoErmasi 2220
#5 KSokolov 1775
Recent Solves
Greatest Common Divisor RomDaph3105
Parameter Injection onta
Successive Powers wywyt213
RSA Decryption Deyerli
Modular Square Root synackrst
Recent Solutions
Quadratic Residues synackrst 0
Modular Inverting synackrst 0
Broken RSA boge 0
Logon Zero richwas 0
Missing Modulus Dagurb 0

Level Up

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